1. Field of the Invention
The present invention relates to an air conditioning apparatus for a vehicle, which can respectively independently adjust temperature of air blown toward a driver's seat side and air blown toward a passenger's seat side next to the driver's seat, or can be respectively independently adjust a temperature of air blown toward a front seat side and air blown toward a rear seat side in a passenger compartment.
2. Description of Related Art
Conventionally, in an air conditioning apparatus where a temperature of air blown toward a front seat side and a temperature of air blown toward a rear seat side in a passenger compartment are respectively independently controlled, a ratio between an amount of air blown toward the front seat side and an amount of air blown toward the rear seat side of the passenger compartment (hereinafter, the ratio is referred to as "air amount ratio") is set to a predetermined value in each air outlet mode such as a face mode, a bi-level mode, a foot mode, a foot/defroster mode and a defroster mode.
However, when the air amount ratio is set at a predetermined value in each of the face mode, the foot mode or the defroster mode, the air amount ratio in the bi-level mode and the face/defroster mode cannot be adjusted if air outlet doors are placed at the same positions and a pressure loss (i.e., air flow resistance) in an air passage for the front seat side is different from that in an air passage for the rear seat side. Alternatively, when the air amount ratio is set at a predetermined value in the bi-level mode or foot/defroster mode, the air amount ratio in the face mode, the foot mode or the defroster mode cannot be adjusted.
To overcome such a problem, an air conditioning apparatus for a vehicle is described in JP-U-4-83811. In the conventional air conditioning apparatus, air outlet ducts having front face and front foot outlets for blowing conditioned air toward the front seat side are connected to an air conditioning case, and air outlet ducts having rear face and rear foot outlets for blowing conditioned air toward the rear seat side are connected to the air conditioning case. When the bi-level mode is set at the front seat side in the passenger compartment, each of two kinds of plate-like doors is set at an intermediate position to open both the front face air outlet and the front foot air outlet. On the other hand, when the bi-level mode is set at the rear seat side in the passenger compartment, one kind of an air outlet door is set at an intermediate position to open both the rear face air outlet and the rear foot air outlet. In the conventional air conditioning apparatus, the plate-like air outlet doors have different shapes in the front seat side and the rear seat side, resulting in an increased production cost.